I find that if I relate my run-of-the-mill, state issued license plate characters to words/phrases then I can remember them better.
Mine:
'75 Merc: Very Agressive Girl - 747 (by Boeing)
'87 Jeep: Doctor of Veterinary Medicine - 936 (9-3=6)
'67 'Stang: 890-KZKM (an AM radio station west of the Mississippi)
We’ll do a different thread some other time for the vanity plates.
I will now quickly display my immature sense of humour. 
My car, a Hyundai Sonata: DHV-422 - We very frequently refer to that as the Dickhead Vehicle… and the 422: 4 = 2+2.
I forget my parents’ van’s license plate numbers, but the first three letters are DKF, which a friend of mine immediately read as Donkey Kong Flatulence.
My sister just called & cracked me up. Her truck has the plate FRA - 007, which she says stands for
Fat Red Ass Bondmobile 
'02 Grand Am GT - JHX-979.
I thought about what that could possibly mean, then it hit me.
Jimi Hendrix died in September 1979!
No, wait, it was June 1970 or so.
Of course, with this firmly entrenched in my mind, I know that some classic rock radio station will call me out of the blue and offer me a million dollars if I can tell them when Hendrix died, and I’ll muck it all up.
698 JSM
Think porn.
MHU-###
Evil Mad Scientist Laugh “Mhu-ha-ha-ha-ha-ha-ha!”
When I received the plates for my last car my best friend and I nearly died with laughter. Dealer asked if the numbers were significant and we laughed harder.
GWF ###
Gay White Female – I am a state sanctioned lesbian! I couldn’t have picked out a better plate if I had tried.
Mine is EWW ####. My first-ever new, new car and I get “Eww”!?!?!?!
A friend of mine’s (who is 19) mum has a license plate that starts with PNV.
My friend sees it as Paul Needs Vitamins or something like that. Her mum (who is in her 40s, and supposedly more mature) sees it as Penis Near Vagina.
Notice I said “or something like that” to Paul Needs Vitamins, because once she told me Penis Near Vagina, I can’t remember anything else clearly. 
A guy I fly with has AHCK ###!
Sort of like, the exclamation before you run into the deer. That’s car’s been in its share of accidents, of course.
YME-##81
Why Me? I was born in 1981.
Our truck:
688 Slovakian Enema Testers
My ex-fiancee’s is YKY-####. I’m always picturing it as “Why KY?”, to which the obvious answer is, “’'cause it hurts when you put it in without it.”
I once had…
QST 069
…looked at it as Quest O’
Mine’s easy to remember… GZR. Geezer.
Makes me feel kind of old.
My own plate isn’t too interesting (JZN-39G, ideas anyone?) but I’ve noticed that, within the last four years, New Jersey has issued plates beginning in JFK, LBJ and MLK…three of the most widely known sets of initials. Incidentally, FDR plates would have been issued in around 1989 by my calculations, but I’ve never seen an FDR plate.
-Andrew L
LKZ ###
Lazy…krappy…zebra?
My brother got, by chance, 1WAW000. So when he got the extra car for the perfect niece he got the vanity plate WAWOOIE. FWIW.
As I sit here, reading this thread, it occurs to me that I am merely an Alt+Tab away from the screen which allows me access to DOR/DMV records in all 50 states.
If I was an evil naughty bad person, I could put every one of you on Jack Chick’s mailing list.
But I’m not.
So I won’t.
Carry on.
Marlitharn that’s not available online to regular shmucks, is it?
My own license plate is EWE-#411. Yup, that’s right – I’m the lost sheep.